Believer was the crazy-killer (one of them anyway) last night. The working theory is that he was possessed in some fashion, though I guess it hasn't been entirely ruled out that he did it of his own volition. Secondary to that theory is that the possession made him stronger (strong enough to survive an attack by the other crazy-killer).
Which implies by the way that both are not controlled by the same person, though for all I know that's some sort of elaborate fakery, too.
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